Optical fiber is a flexible transparent fiber made of silica or plastic. Optical fiber has become a valuable component of electronic devices, as it permits for longer transmission distances and higher bandwidth than cable wires. Despite the many benefits of optical fiber, one of the main drawbacks is the fragility of the fiber, as compared to cable wires. Optical fiber can be used in a number of applications, including as a medium for telecommunication and computer networking, sensor applications, and power transmission. As the number of applications increase, there is a growing demand for mechanisms that repair optical fiber. Existing mechanisms for repairing optical fiber include fusion splicing and mechanical splicing.
Fusion splicing is the act of joining two optical fibers end-to-end using heat (e.g. via electric arc, laser, gas flame, etc.). One goal of fusion splicing is to fuse the two fibers together in such a way that light passing through the fibers is not scattered or reflected back by the splice. Another goal of fusion splicing is to create a splice and surrounding region that are almost as strong as the original fiber itself. Fusion splicing is a widely accepted form of repairing optical fiber; however, fusion splicing cannot be used in many situations. In applications that are sensitive to heat, such as environments with electronic components, particularly in a military aircraft environment, fusion splicing may not be a viable option. Fusion splicing can also be problematic in explosive environments. For example, a fueled aircraft could have an increased chance of explosion due to combustible fumes in the vicinity of the splice.
Existing mechanisms for mechanical fiber splices are designed to be quicker and easier to install than fusion splicing; however, there is still the need for stripping, careful cleaning, and precision cleaving of the optical fibers. Currently, fiber ends are aligned and held together by a sleeve or a high precision capillary tube, often using a resin or clear index-matching material that enhances the transmission of light across the joint. Such joints typically have higher optical loss and are less robust than fusion splices, especially where imperfect contact is made between the two optical fiber ends within the resin.
U.S. Pat. No. 7,410,308, issued on Aug. 12, 2008 and entitled “Fiber Optic Cable Splice,” addresses fiber optic cable splices; however, this solution only addresses splicing cables with one strength member. Furthermore, currently, no fiber optic mechanical splice is qualified to the Aircraft Mechanical Splice Military Specification (MIL-PRF 24623/7), which is incorporated herein. In addition, currently all aircraft fiber optic cabling is being repaired by replacement on a case-by-case basis. Thus, there is a need for a fiber optic mechanical splice that meets these requirements.